Most musical instruments look a little weird, if you stare at them for long enough. When aliens finally make contact, they'll be confused by our habit of gripping wood and metal structures and throttling sound out of them. But some devices are odder than others. Here are the strangest musical instruments of all.

The Contrabass Balalaika

The Russian folk instrument was developed in the late 17th century. It's available in various sizes (prima, secunda, alto, bass and contrabass balalaika) — but they all have a triangular body, played with fingers or leather plectrums.

The American Fotoplayer

The instrument combines a piano with organ pipes, drums, bells and various sound effects, using switches, pedals, levers, buttons and pull chords. It can chirp like a bird, or create the sound of thunder, pistol shots or sirens, among others. Some of them have a matching roll cabinet that features music specially composed for romantic, dramatic or chase scenes with "Picturolls."

These were produced between 1912 and 1925. Between 8-12,000 of these were made, but less than 50 survive, and only 12 are known to be in playing condition.

Pikasso Guitar

The Theremin or the ætherphone

The theremin, one of the first electronic musical instruments, was invented by the Russian Lev Sergeyevich Termen (Léon Theremin) in 1928. It's an instrument that you play without making any physical contact at all.

Cimbalom

The concert hammered dulcimer was popularized in Hungary, but can be found in other Central-Eastern European countries and Greece, too. It's very common amongst the Romani people (Gypsies) of the area. The cimbalom has occasionally been used in film scores like The Lord of The Rings: The Two Towers, The Curious Case of Benjamin Button or in the Star Trek III: The Search for Spock.

Crwth

The Great Stalacpipe Organ, Luray Caverns, Shenandoah National Park, Virginia

The electrically actuated lithophone (an instrument consisting of a rock or pieces of rock) was designed in 1956 by a Pentagon programmer named Leland W. Sprinkle, but the musical attributes of the stalactites was known since the discovery of the caverns in 1878. Each organ key is wired to a solenoid-actuated rubber mallet that is connected to a stalatite.

The Ondes Martenot (or the ondium Martenot, or ondes musicales)

The early electronic musical instrument was invented in 1928 by Maurice Martenot. The notes are produced by varying the frequency of oscillation in vacuum tubes. It was produced until 1988.

Frank Zappa, Arthur Honegger and Pierre Boulez employed the Ondes Martenot in their works, and it was frequently used in popular films and TV series like The Outer Limits (1963-1965), Lawrence of Arabia (1962), Ghostbusters (1984) and Amélie (2001), among others.